Jiang Pengqiang, Peng Yang, Mou Yun, Cheng Hao, Chen Mingxiang, Liu Sheng
Appl Opt. 2017 Oct 1;56(28):7921-7926. doi: 10.1364/AO.56.007921.
In this paper, we propose a thermally stable multi-color phosphor-in-glass (PiG) for chromaticity-tunable white light-emitting diodes (WLEDs). The multi-color PiG has a red, green, and blue (RGB) phosphor glass layer, which was screen-printed and co-sintered on a glass plate with a low temperature of 600°C. The WLED with ultra-compact structure was fabricated by the RGB-PiG directly bonded on a flip-chip ultraviolet (UV) LED. By controlling the weight ratio of R∶G∶B phosphors, the thickness of the RGB layer, and the weight ratio of phosphors to glass powders (PtG), the chromaticity of RGB-PiG based WLEDs can be effectively tuned with high color quality. With the R∶G∶B ratio of 2∶3∶2, the RGB thickness of 75 μm, and the PtG ratio of 2∶1, the RGB-PiG based WLED achieves a natural white light with a luminous efficacy (LE) of 27.8 lm/W, a correlated color temperature of 4245 K, and a color rendering index of 92.6 at the current of 350 mA. The LE losses of the RGB-PiG based and RGB phosphor-in-silicone based WLEDs are 4.7% and 14.6% after the aging tests of 1000 h at 100°C, respectively. The results demonstrate that the multi-color PiG is a promising converter for UV-excited WLEDs.
在本文中，我们提出了一种用于色度可调白光发光二极管（WLED）的热稳定多色玻璃中磷光体（PiG）。这种多色PiG具有红色、绿色和蓝色（RGB）磷光体玻璃层，通过丝网印刷并在600°C的低温下在玻璃板上共烧结而成。具有超紧凑结构的WLED是通过将RGB-PiG直接键合在倒装芯片紫外（UV）LED上制成的。通过控制R∶G∶B磷光体的重量比、RGB层的厚度以及磷光体与玻璃粉末的重量比（PtG），基于RGB-PiG的WLED的色度可以在高色品质下得到有效调节。当R∶G∶B比例为2∶3∶2、RGB厚度为75μm且PtG比例为2∶1时，基于RGB-PiG的WLED在350mA电流下实现了自然白光，发光效率（LE）为27.8lm/W，相关色温为4245K，显色指数为92.6。在100°C下进行1000小时的老化测试后，基于RGB-PiG的WLED和基于硅树脂中RGB磷光体的WLED的发光效率损失分别为4.7%和14.6%。结果表明，这种多色PiG是用于紫外激发WLED的一种有前景的转换器。
